In technical field of reference, devices are known, which are used for the orientation of an optical element. Especially, though not exclusively, these devices can be used for the motor-driven control of the direction of a beam of light in the space.
One of the possible fields of application of these devices is—for example—that of laser (micro)surgery.
In particular, in the technical field of reference, devices of the type mentioned above are known, which are manually operated, so as to orient—in the space—a mirror that causes the light beam to converge and points it based on its position.
This type of devices is affected by numerous drawbacks, like for example that of not being provided with a motor-driven system and that of not being able to be controlled in an assisted fashion by a processor. This leads to the drawback of not being able to improve surgical quality in terms of precision and safety, thus precluding the application of some techniques, such as the automatic execution of scanning motions, of tremor filtering, of motion scaling as well as the adoption of customized control interfaces.
U.S. Pat. No. 5,966,991 discloses the use of a two degree-of-freedom spherical orienting device, which comprises a mechanism, which is operated by a pair of rotary actuators, which, in turn, are fixed to a support structure. This concept was taken up, with some changes, also in the more recent patent publication EP 2 256 397 A1.
However, the aforesaid configurations of devices using rotary motors are affected by different drawbacks.
One drawback is due to the fact that they are not suited to be used in combination with optical elements that can be passed through by a light beam (also known as see-through elements), since the mechanisms used are provided with rotary assemblies that interfere with the trajectory of the incident light beam that is suited to interact with the optical element. In particular, known mechanisms are also affected by the drawback of obstructing—or being an obstacle for—the line of sight of an observer wanting to see through the optical element (typically, from the top to the bottom or, anyway, in a direction that is substantially orthogonal to the light beam).
A further drawback results from the fact that the rotation of the motors strictly depends on the gear ration chosen. For example, for given gear ratios, the precision in the positioning of the optical element can be very high, but, in this case, it decreases the maximum reachable speed, and vice versa.
DE 10 2012 012 780 A1 describes a mirror system to deflect a laser beam. The system described therein comprises a suspension device to support the mirror, so as to allow it to rotate around two orthogonal axes, and an operating device to move the mirror. The suspension device has a first inner frame, where the mirror is held so as to be able to rotate around a first axis, and a second outer frame, where the first inner frame is held so as to be able to rotate around a second axis. The operating device is provided with two linear actuator units, each coupled in an articulated and symmetrical manner relative to the other one. The two linear actuators are arranged at a distance from one another, substantially extend in parallel directions and can be controlled separately, so as to carry out a rotation of the mirror in a desired position.
However, even the system described in the prior art document discussed above is affected by the same drawbacks mentioned above.